The invention relates to a device and a method for inspecting hollow spaces having the features recited in the preamble of claim 1.
The DE-C-40 31 715, DE-A-38 03 274, DE-U-91 05 211 and DE-C-42 29 787 disclose methods and devices for inspecting conduits by image transmission that permit to introduce a second camera system into pipes branching from the main pipe using the assistance of a carriage located therein. Nozzles are also known to be used for cleaning sewers in which the outlet openings are arranged in such a manner that they are capable of supplying the thrust necessary to draw along a supply hose. These pipe cleaning nozzles are also known to be used as a driving element for introducing inspection cameras. However, the heretofore known techniques do not permit the inspection of very long lines with small dimensions, the wheel-driven camera being no longer able to pull the cable. In addition, these techniques are not capable of circumventing obstacles and branch lines are still difficult to inspect. Although the above mentioned method, which is directed to introduce second cameras into the branch lines, solves the problem of inspecting such branch lines, it does not allow to overcome obstacles. Furthermore, the expense of technical requirements and staff is increased since two camera systems have to be monitored.
Therefore, it is an object of the present invention to provide a device and a method for inspecting hollow spaces such as conduits and the like that permit to introduce a base member carrying a camera into branch lines and by means of which obstacles may be overcome. It is another object of the invention to make it possible to make for any desired location in large containers or buildings by means of the device according to the invention.
The solution to this object is achieved by the features recited in the characterizing part of claim 1. Developments and advantageous embodiments of the invention are comprised in the other claims.
According to the invention, a device for inspecting hollow spaces such as pipes, conduits, buildings or containers and consisting of a probe with a built-in camera whose objective is oriented toward a front end of a base member of the probe, of a hose line for supplying a liquid or gaseous medium to the probe, said line being connected to the back end of the base member of said probe, of a supply unit for the hose supply line which is situated outside the site of utilization of the probe, of at least one outlet nozzle for the medium which is located on the probe, and of transmission means which are provided between the camera and an evaluating and/or imaging unit, is characterized in that at least three rotatable outlet nozzles for the medium are arranged on the periphery of the base member between its front and back end, the axis of the jet of the medium being angled at an angle of 0xc2x0 to 45xc2x0 from the central longitudinal axis between the front and back end of the base member.
There are preferably provided four rotatable outlet nozzles whose axes of rotation are offset by 90 degrees across the central longitudinal axis of the base member. The outlet nozzles are preferably rotatable 360 degrees and are driven by at least one electric servomotor.
Outside the hollow space to be inspected, a control and feeding cable is arranged between the servomotor and a control unit.
The rotatable outlet nozzles are preferably in the shape of a disk or of a flat cone and are non-rotatably carried on axles that are arranged at right angles. Preferably, the respective outlet openings of the nozzles are arranged on the periphery of the disk or flat cone, respectively.
The axles are preferably devised as hollow axles for the transportation of the medium from the hose supply line to the outlet nozzles and the axes of the jet of the medium exiting the outlet openings are oriented toward the respective one of the central longitudinal axes of the hollow axles.
According to a particular embodiment of the invention, the probe is equipped with a gyrometer. According to other advantageous realizations of the invention, further testing and measuring instruments and/or sensors are arranged, in addition to the camera, in or on the base member.
A method for inspecting hollow spaces such as pipes, conduits, buildings or containers in accordance with the invention involves the following steps:
connecting a probe according to the claims 1 through 11 to a supply unit with a liquid or gaseous medium by means of a hose supply line,
introducing the probe into the hollow space to be inspected,
admitting a pressurized medium into the probe,
controlling the rotatable nozzles by way of the control cable such that the probe is held in the free space on one side and that, on the other side, a recoil force develops, advancing the probe into the respective hollow space and evaluating the results.